The field of the disclosure relates generally to security systems that utilize voice recognition, and more specifically, to methods and systems for speaker identity verification.
Security is a major concern for many and draws significant investment from both military and commercial endeavors. Identity verification is a key capability for many aspects of security. Speech-based identity verification is one of the least objectionable biometrics. However, an open issue with this biometric, computerized Speaker Identity Verification (SIV) is the threat of replay attacks.
A speech signal is quite complex and every natural utterance is unique. By focusing on speaker-specific characteristics of the speech signal, individual speakers can be distinguished. In producing speech, the human body performs many complex and coordinated tasks. When the result of all these tasks is reduced to a one-dimensional audio signal, the result is easily captured and replayed with high fidelity.
Previous attempts to address the replay attack issue have focused on determining the liveness' of the source by referring to additional signal data, for example, a two dimensional video of the speaker's face. However, modern video capture and replay technology makes such liveness testing also susceptible to spoofing.